Heat recuperative catalytic oxidation device

Abstract

An oxidation assembly catalytically oxidizes organic hydrocarbon gases and recovers the heat held by the heated oxidized exhaust generated by such oxidation. The assembly includes a preheater and a catalytic recuperative heat generator which contains a suitable oxidation catalyst. An outside air inlet provides communication between the outside air and the heat generator. The assembly also includes a fan having a first and second outlet for moving the heated oxidized exhaust, and an outside air preheat exchanger. The first outlet of the fan and a recirculation duct communicate to form a loop for storing the heated oxidized exhaust for later use, and the second outlet of the fan and the inlet of the catalytic preheater communicate to form a loop for returning the oxidized exhaust to the preheater. Although the assembly may be designed with a fixed pre-adjusted gas flow control device, in the preferred embodiment, variable flow control devices are provided at various positions within the apparatus.

I claim: 
     
       1. A catalytic oxidation assembly comprising, in combination: a preheater;   catalyst means having an inlet duct communicating with said preheater, a catalyst, and an outlet;   a recirculation duct having an inlet communiating with said catalyst means outlet, and an outlet;   gas moving means having an inlet, a first outlet, and a second outlet;   means for providing communication between said gas moving means inlet and said recirculation duct outlet, and means for providing communication between said gas moving means first outlet and said recirculation duct inlet;   an ambient air preheat exchanger having first and second passageways in thermal communication with each other, means for providing communication between the ambient and said gas moving means inlet, which includes said first passageway, and means for providing communication between said catalytic heat generator means outlet and the ambient which includes said second passageway;   return means for providing communication between said gas moving means second outlet and said preheater; and   exhaust means for providing communication between said catalyst means outlet and the ambient.   
     
     
       2. The catalytic oxidation assembly as defined in claim 1 wherein said recirculation duct further includes gas flow control means. 
     
     
       3. The catalytic oxidation assembly as defined in claim 1 further including gas flow control means in said gas moving means first outlet. 
     
     
       4. The catalytic oxidation assembly as defined in claim 1 wherein said catalyst means comprises: a hood receiving at least a portion of said catalyst means inlet duct;   said catalyst being positioned in said hood and surrounding at least a portion of said catalyst means inlet duct, and forming a catalyst layer between said hood and said catalyst means inlet duct;   an ambient air inlet duct for providing communication between the ambient and said hood.   
     
     
       5. The catalytic oxidation assembly as defined in claim 4 wherein said ambient air inlet duct further includes gas flow control means. 
     
     
       6. The catalytic oxidation assembly as defined in claim 1 wherein said means for providing communication between the ambient and said gas moving means inlet further includes gas flow control means. 
     
     
       7. The catalytic oxidation assembly as defined in claim 1 wherein said preheater comprises a catalytically active grid. 
     
     
       8. The catalytic oxidation assembly as defined in claim 1 wherein said preheater comprises a plurality of catalytically active metallic grids heated by electrical heating means and separated by a plurality of ceramic dividers interleaved with said grids. 
     
     
       9. The catalytic oxidation assembly as defined in claim 8 wherein said dividers are ceramic wool and wherein said metallic grids are enmeshed in said dividers. 
     
     
       10. A catalytic oxidation assembly comprising, in combination: a preheater;   catalyst means having an inlet duct communicating with said preheater, a hood receiving at least a portion of said inlet duct, a catalyst positioned in said hood and surrounding at least a portion of said inlet duct and forming a catalyst layer between said hood and said inlet duct, and an outlet;   an ambient air inlet duct connected to said hood so as to provide communication between the ambient and said hood;   a recirculation duct having an inlet communicating with said catalyst means outlet, and an outlet;   gas moving means having an inlet, and an outlet;   means for providing communication between said gas moving means inlet and said recirculation duct outlet, and means for providing communication between said gas moving means outlet and said recirculation duct inlet; and   an ambient air preheat exchanger having first and second passageways in thermal communication with each other, means for providing communication between the ambient and said gas moving means inlet which includes said first passageway, and means for providing communication between said catalytic heat generator means outlet and the ambient which includes said second passageway.   
     
     
       11. The catalytic oxidation assembly as defined in claim 10 further including gas flow control means in said gas moving means outlet. 
     
     
       12. The catalytic oxidation assembly as defined in claim 10 wherein said ambient air inlet duct further includes gas flow control means. 
     
     
       13. The catalytic oxidation assembly as defined in claim 10 wherein said means for providing communication between the ambient and said gas moving means inlet further includes gas flow control means. 
     
     
       14. The catalytic oxidation assembly as defined in claim 13 wherein said recirculation duct further includes gas flow control means. 
     
     
       15. The catalytic oxidation assembly as defined in claim 10 wherein said preheater comprises a catalytially active grid. 
     
     
       16. The catalytic oxidation assembly as defined in claim 10 wherein said preheater comprises a plurality of catalytically active metallic grids heated by electrical heating means and separated by a plurality of ceramic dividers interleaved with said grids. 
     
     
       17. The catalytic oxidation assembly as defined in claim 16 wherein said dividers are ceramic wool and wherein said metallic grids are enmeshed in said dividers. 
     
     
       18. A catalytic oxidation assembly comprising, in combination: a preheater;   catalyst means having an inlet duct communicating with said preheater, a hood receiving at least a portion of said inlet duct, a catalyst positioned in said hood and surrounding at least a portion of said inlet duct and forming a catalyst layer between said hood and said inlet duct, and an outlet;   an ambient air inlet duct communicating between the ambient and said hood;   a recirculation duct having an inlet communicating with said catalyst means outlet, and an outlet;   gas moving means having an inlet, a first outlet, and a second outlet;   means for providing communication between said gas moving means inlet and said recirculation duct outlet, and means for providing communication between said gas moving means first outlet and said recirculation duct inlet;   return means communicating between said gas moving means second outlet and said preheater; and   an ambient air preheat exchanger having first and second passageways in thermal communication with each other, means for providing communication between the ambient and said gas moving means inlet which includes said first passageway, and means for providing communication between said catalyst means outlet and the ambient which includes said second passageway.   
     
     
       19. A catalytic oxidation assembly comprising: a stack;   a recuperative heat generator positioned in said stack comprising:   plate positioned in and extending across said stack;   an inlet duct passing through said plate;   a hood receiving at least a portion of said inlet duct;   a catalyst positioned in said hood and surrounding at least a portion of said inlet duct and forming a catalyst layer between said hood and said inlet duct;   an ambient inlet duct connected to said hood for providing communication between the ambient and said hood; and   an outlet; and   an ambient air preheat exchanger having first and second passageways in thermal communication with each other, means for providing communication between the ambient and said duct passing through said plate which includes said first passageway, and means for providing communication between said catalytic heat generator means outlet and the ambient which includes said second passageway.